I've been meaning to write short blog posts about the results of the workshops we put on. I got an email asking me about the last one and it reminded me to actually do it. So here it is!
I roped my friend Jim Titus into giving a workshop about guitar pedals since he started building them in his free time. The workshop started out with a presentation which you can download here. Jim talks about the history of guitar distortion which is very entertaining. Then he played some samples of early guitar distortion, there was a country song named "Don't Worry" by Marty Robbins which had an awesome sounding distorted bass. I'm not a country fan, but that part of the song rules. Jim then talked about the distortion circuit and showed some enclosures off (which became important later!)
Then it was build time! We all got our kits and got to work. We all help each other through the build and eventually tested them on Jim's o-scope so we could see the affect the pedal had on a sine wave.
There was an issue when we actually tried to use the pedals without an enclosure: there was no shielding and there was too much noise. Lucky for us one of the folks, Bruce Mulligan, had built an enclosure ahead of time. Bruce and his daughter built up their kit and installed it in the enclosure. After figuring out a grounding issue we had the distortion we were looking for!
Be sure to check out our next workshop, Advanced Microcontroller Audio with Paul Stoffregen